I dug a bit further online and gathered some information. Went and checked my transaxle - there's about a 1/8 inch play/slop on the left axle and a small amount on the right. Clearly, my bushings are shot. I work at a small engine repair shop and the other day I put new belts in the exact same type of tractor (13aj609g766) and I noticed that transmission was FAR quieter and had no slop. So, mine's worn out. I'm gonna get those wheels off with oxygen and acetylene, take the transaxle apart and see if the bushings can be replaced or if she's too far gone (shaft digging into the housing). If its that bad, I'm looking at 350 for a trans. It honestly isn't worth it, but it is, because I already did so much to the thing (all the stuff I mentioned above). Oh well...
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Forgot to hit post and then I went and took out the trans and took it apart. Sure enough, the outer bushings were worn razor thin and the top case is chewed up on the left. I'm attaching some pics, you can see on the right side there's a 'lip' that goes all the way around the top case but on the left it's worn away. Do y'all know if it'll work if I just replace the bushings or will I have to replace the top case? Anyway, I'm gonna probably just try bushing first regardless. Worst case I'm out ~20. If I have issues after that I'll buy a top case but that's another ~70. There was a bunch of metal shavings underneath the differential shaft/main axle, and theres scores on the differentail shaft/axle on the left side where it was grinding on something (probably because of the bushings being bad) but they aren't nearly deep enough to compromise the axle. One of the seals was completely gone, chewed away. Also some light rusting in some areas, weird. If I take the differential/main axle out it has a lot of play but I think that's normal for a differential. I've seen pictures of new ones with slop like that. So, hopefully a thorough cleaning of the casing and gears, with new bushings and seals and grease, will save this thing.
Good Side of Top Case (Right)
Bad Side of Top Case (Left)
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Worn Out Bushing

Scored Axle

Metal Shavings in Case
